In a small bowl, whisk together the red wine vinegar, soy sauce and pineapple juice. Set aside.
Preheat a large cast iron skillet over medium heat. Add the spam and cook for a few minutes until lightly browned, stirring occasionally. Remove from the skillet and set aside.
Add the olive oil to the skillet and heat. Add the eggs to the skillet and stir to scramble. Once the eggs start to cook, stir in the rice. Stir constantly until the eggs are nearly done. Stir in the spam and pineapple.
Stir in half of the green onions. Stir in the sauce mixture.
Top with the remaining green onions and serve hot.